The speed of light in a material is given by:

where

is the speed of light in vacuum
n is the refractive index of the material
The lens in this problem has a refractive index of n=1.50, therefore the speed of light in the lens is

And the correct answer is C).
Answer:
r = √ x² + y² and θ = tan⁻¹ y / x
Explanation:
The polar coordinates are obtained by transforming the Cartesian coordinates (x y) into others (r tés), for this we use to find r the Pythagorean theorem
r = √ x² + y²
To find teas we use trigonometries
tan θ = y / x
θ = tan⁻¹ y / x
In general the angle can be given in any unit, but the most used in physics is in radians
Answer:
Most of the oxygen in the atmosphere is in the form of O2, which means it is made up of molecules containing two oxygen atoms. Ozone, however is O3, which means it is made up of molecules containing three oxygen atoms. O2 is what we breath, and what plants release from photosynthesis. Ozone occurs naturally high in the stratosphere, where it absorbs ultraviolet light, protecting us here on the surface from skin cancer. Ozone can also occur closer to the surface of the earth as a pollutant. It is formed from reactions with O2 and chemicals emitted from factories and cars. It comes in the form of smog.
So in general:
Oxygen (O2): Essential to human life
Ozone (O3) in the stratosphere: essential to protecting life on earth
Ozone (O3) on the surface of the earth: toxic to human life, caused by pollution
Answer:False
Explanation:
Work is being done on a body when it causes displacement of body on the application of force

When we pull the door by a force it causes zero displacements of the door. So we can say that work done on it is zero.
Thus the above-given statement is false
Sound waves....................................